"Insistent as anesthetic": Difficult similes subserving the poetic context

Previous research has identified a type of nonstandard simile in which the ground is a non-salient feature of the source term (for example, the nonstandard hard as a lamp as opposed to the standard hard as a rock), and found this type to be common in poetry and much rarer in non-poetic discourse. Since these nonstandard similes entail a fundamental semantic breach and violation of a basic convention of the simile, how can their existence be explained? Here we claim that it is the poetic context itself, the poem within which these similes appear, which is the key to explaining their existence and their unique advantage. Through a series of poetic examples, including poems by Plath, Lee, and Rukeyser, we show how the semantic difficulty of the nonstandard simile serves the poem and fulfils various functions within it.